Abstract

Background and objective: Aspergillus clavatus is an opportunistic human pathogen causing invasive aspergillosis. It is an economically important species because it can grow on rotting fruit(apples)and stored food products and able to produce a variety of mycotoxins. It has only been known to reproduce mitotically. This study aimed to discover the sexual reproduction in A. clavatus.

Results: There were similar ratios of the two mating types (45% MAT1-1 n = 9, 55% MAT1-2 n = 11). A. clavatus possesses a functional sexual cycle with mature cleistothecia fawn to brown/yellow in color, containing heat-resistant ascospores, produced after four weeks incubation at 25˚C and 28˚C on Nescofilm- sealed oatmeal agar plates. The cleistothecia contain hyaline ascospores that have two equatorial ridges. Recombination, leading to increased genotypic variation demonstrated in the ascospore offspring using molecular markers.

Conclusion: The ability of A. clavatus to undergo sexual reproduction is highly significant in understanding the biology and evolution of the species. The presence of a sexual cycle provides an invaluable tool for classical genetic analysis and will facilitate research into the genetic basis of pathogenicity and fungicide resistance.